Electric heater



(No Model.)

F. A. JOHNSON.

ELEGTRIG HEATER.

N0. 576 347. Patented Feb. 1897.

Y gvwewtoz witmww M NH g I L W v How mags UNITED STATES PATENT OFFICE.

FREDERIC AYRES JOHNSON, OF BINGIIAMTON, NE\V YORK.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 576,347, dated February 2, 1897.

Application filed February 24, 1896. Serial No. 580,420. (No model.)

To all whom it may concern.-

Beit known that I, FREDERIO AYRES J OHN- SON, a citizen of the United States, residing at Binghamton, in the county of Broome and State of New York, have invented certain new and useful Improvements in Electric Heaters, of which the following is a specification.

My invention relates to electric heaters, and has for its objects to improve and simplify the construction thereof; and to these ends it consists in a heater embodying the features of construction and mode of operation substantially as hereinafter more particularly set forth.

Referring to the accompanying drawings, wherein I have illustrated one simple and convenient form of heater embodying my invention, Figure 1 is a longitudinal sectional view of a heater and a connector embodying my invention. Fig. 2 is an end view of the heater, and Fig. 3 is an end view of the connector.

In the drawings, 0 represents a coil of insulated copper wire, for instance, shown in the form of a solenoid and connected to proper terminals, by means of which it may be included in an electric circuit. This coil of insulated wire C may be formed in any well-known manner, and is preferably supported upon a suitable spool A, which is preferably of insulating material and is also preferably covered with an outer case B of similar material. This spool and case form a casing inclosing the coil or conductor 0, leaving an opening 0 within the coil into which the curling-iron or other article to be heated may be inserted.

Surrounding the coil G is a shell S of iron, preferably laminated, the direction of the laminze coinciding with the lines of magnetic force.

Such, in brief, is the general construction of the heater, and it is desirable to so arrange it that it can be readily connected with the ordinary terminals of an electric-lighting system, and for that purpose I provide a connector adapted to fit the ordinary incandescent-lamp sockets or other terminals of an electric system. Thus in the present instance I have arranged the terminals of the coil C at one end of the case and extend the terminals in the shape of segments F. The case also is provided with a threaded nipple N. The connector H in the present instance consists of a body of insulating material having terminals h h, (shown in the present instance as a pin and ring, respectively, although, of course, they may be any of the standard terminals to fit ordinary sockets.) Connected with these terminals are the wires 2', which are in turn connected with pins E E, mounted in the insulating material of the connector, and there is a screw threaded opening G, adapted to fit the screw-threaded nipple N of the heater. It will be seen from this construction that when the nipple N is screwed into the opening G the terminals F E of the heater will contact with the pins E E of the connector, and when the connector is applied to the ordinary socket of an electric distributing system the circuit is completed in the usual way. This makes a convenient connector, so that the heater may be applied to any existing system, but of course any other well-known means of connecting the heater to the distributing system may be used.

My heater is adapted to be used in connection with ordinary alternating-current-distributing systems, and when it is connected to the terminals of such a system the currents passing through the coil 0 produce rapid alternations therein in the usual manner. When the curling-iron X (shown in dotted lines, Fig. l) or other metallic device is inserted within the coil, an alternatingmagnetic field is generated in the iron, and it quickly becomes heated bythe induction of eddy-currents in itself and by the attendant phenomena known as hysteresis, magnetic friction, 850., and all these phenomena tend to rapidly heat the metal of the curling-iron or other device. The iron shell S surrounding the coil adds to these inductive effects, and curling-irons and similar devices can be rapidly heated under the above conditions. Of

induction in the device itself.

will be seen that this device is advantageous, in that it does not depend upon. the heating of the coil or conductor itself and the radia tion or conduction of such heat therefrom to the article being heated, but that the heat is generated in the article itself, as before stated, and the coils are not unduly heated. Furthermore, the size of the heater is greatly re duced, and when it is intended for heating curling-irons and similar small articles it can readily be carried about, and by means of the connector attached to any alternating-current-distributing circuit bysubstituting it for an incandescent lamp or other device.

It is preferable, of course, to have the connector form a part of the heater, as shown in the drawings, but it will be understood that any other way of connecting the heater with the source of current may be utilized.

It will be seen that in the use of my device the article being heated. may be said to form a part of the heater itself, in that the translation or conversion of energy into heat takes place in the article being heated to a greater or less extent. Further, it may properly be termed a magnetic-induction heater, in that it depends not upon the direct conversion of the electric energy into heat due to the resistance in the coil itself, but to the magnetic induction produced by the current, which in turn, owing to the eddy-currents, hysteresis, magnetic friction, &c., of. said magnetic-induction currents, produces heat in the article itself.

hat I claim :is-

1. A magnetic-induction heater, comprising a case having an opening to receive the article to be heated, a coil surrounding the opening, alaminated magnetic shell surrounding the coil and a connector, whereby the heater may be connected to an ordinary alternating-eurrent circuit, and the article to be heated applied in the opening and heatml in the manner set forth.

2. A n1agneticdnduetion heater comprising a case of insulating material, consisting of a spool and an outer covering, a coil of insu lated copper Wire surrounding the spool, a shell of laminated iron surrounding the coil and inclosed in the ease, terminals of the coil in the form of segments on the exterior of the case, a connector of insulating material applied to the case and having terminal pins bearing on the segments, and provided with contacts adapted to fit the ordinary lampsockets, substantially as described.

in testimony whereof I have signed my name to this specification. in the presence of two subscribing witnesses.

FREDERIC AYRES .TOI IXS( )X.

Witnesses: 

